i can not find the temp control sensor? can this sensor go bad and cause my car to run really rich and cause my fan to stay on constantly while running> thanks

The Engine Coolant Temp Sensor (ECTS) can cause all sorts of weird things to happen, depending on the mode of failure.

The sensor itself is located on the side of the engine nearest the driver. It has two wires going to the sensor. Make sure the engine is cold when you replace it, otherwise you run the risk of being burnt by the coolant. Wrap the threads of the new sensor with Teflon tape before you install it. Consider replacing the connector on the end of the wires at the same time, as they can become corroded and not make proper contact. When you buy the new sensor, make sure the tip is all metal. Some early ones had resin-tipped elements, and they were not up to the task ...

I have a 2002 Saturn L200 and I am having a similar problem. The fans on both </span>the front and back side of my radiator run constantly only when the engine is running. There are no other symptoms and I was wondering if this is the ECTS or would this be some other problem? Also, I am not getting a check engine light or anything else.
Edited by: ketev

It most likely is the ECTS.